Games like forma.8
Games like forma.8 include Hollow Knight, Hollow Knight: Silksong, Dust: An Elysian Tail, Ori and the Will of the Wisps, and Crimson Desert Enhanced. We matched them by the tags players give forma.8 on Steam (Indie, Action, Adventure, Exploration, and 2D): closest matches first, and among equally close ones the better-known games.

Hollow Knight
Shared: Indie · Metroidvania · 2D

Hollow Knight: Silksong
Shared: Indie · Metroidvania · 2D

Dust: An Elysian Tail
Shared: Action · Indie · Adventure

Ori and the Will of the Wisps
Shared: Action · Metroidvania · Adventure

Crimson Desert Enhanced
Shared: Action · Exploration · Adventure

Gato Roboto
Shared: Indie · Action · Adventure

Skul: The Hero Slayer
Shared: Indie · Action · 2D

Monster Boy and the Cursed Kingdom
Shared: Action · Indie · Adventure

Rise of the Tomb Raider™
Shared: Action · Adventure · Singleplayer

ICEY
Shared: Action · Indie · Adventure

Fallout 4
Shared: Exploration · Adventure · Singleplayer

Terraria
Shared: 2D · Adventure · Exploration

SteamWorld Dig 2
Shared: Indie · Adventure · Action

The Vagrant
Shared: Action · 2D · Adventure

UnEpic
Shared: Indie · Action · Metroidvania

Axiom Verge
Shared: Indie · Action · Metroidvania

Slime Rancher
Shared: Adventure · Exploration · Singleplayer

Rogue Legacy
Shared: Indie · Action · Singleplayer

Marvel’s Spider-Man Remastered
Shared: Action · Adventure · Open World

STAR WARS Jedi: Survivor™
Shared: Action · Adventure · Singleplayer

Rogue Legacy 2
Shared: Action · Indie · Metroidvania

Dungeon Munchies
Shared: Indie · Action · Adventure

Hob
Shared: Action · Adventure · Indie

Prince of Persia The Lost Crown
Shared: Action · Exploration · Metroidvania